Evaluation of Systolic Function Flashcards
Week 6
This is what the ventricles have in them prior to the atria emptying into the ventricles.
Preload
According to ____, increasing initial muscle length will result in no change or a reduction in the force of contraction.
Frank-Starling law
As preload ____ the LV fibers will lengthen in diastole and the force of systolic contraction will ____.
Increases; increases
____ is commonly estimated as EDP (or end-diastolic pressure or volume).
Preload
The ability of the heart to contract is affected by:
Afterload and Contractility (inotropic)
The force ventricles face when contracting in systole
Afterload
Afterload is ____ related to ventricular systolic pressure, ventricular radius, and is ____ related to ventricular thickness
Directly; inversely
An increase in afterload will result in a reduced ventricular force and velocity of contraction, leading to an ____ in end systolic volume. Causing the ventricle to thicken
Increase
The force or energy expended on the heart muscle resulting in contraction.
Contractility (inotropic)
Dobutamine is an example of a positive ____ agent.
Inotropic
____ ____ (chronotropic) is expressed as beats per minute (BPM).
Heart rate
A heart rate of < 60 BPM is considered ____.
Bradycardia
A heart rate of > 100 BPM is considered ____.
Tachycardia
Increase HR = ____ CO
Increase
What is the formula for CO?
CO = Stroke volume (SV) x HR
Intrinsic contractility is the intensity of its active state, or how much ____ is available and actin-myosin interactions.
CA+
With higher heart rate, calcium levels may be higher within the muscle cells, and therefore the force of contraction will ____.
Increase
How to we quantitatively measure RV systolic function?
- Measure a length and width of the RV when enlarged
- RV TDI (Measure the S’)
When measuring RV TDI, S’ > ____ cm/s represents normal RV function
10 cm/s
For a Quantitative assessment of the LV use:
- M-mode at the mid-papillary level
- Teichholtz
- Simpsons
- Doppler if MR is present (dP/dt)
____ measures of the rate of rise of ventricular pressure during IVCT.
dP/dT
dP/dT is calculated by dividing the change in ____ by the change in ____.
Pressure; time
If left ventricular systolic function is normal, dP/dt would be > ____.
1200 or .27 msec.
If left ventricular systolic function is mild-moderately dysfunctional, dP/dt would be ____.
800-1200
